An "obsessed" stalker repeatedly rammed his girlfriend's car until it spun off the road and crashed into a traffic light.
The terrified victim, 17, called the police as Shaun Dale Allan's Vauxhall Astra kept shunting into the back of her Corsa as she drove home from work at night.
The shaken-up teenager suffered a cut palm on her hand in the crash, which happened at the end of the 20-minute pursuit.
Allan (30) also sent her a barrage of text messages and kept turning up at the pub where she worked, for several weeks after they split up.
He admitted stalking his ex-girlfriend, between June 8 and July 3 this year.
Leicester Crown Court was told Alan, formerly of Kirk Lodge hostel, London Road, Stoneygate, Leicester, has previous convictions for harassing and assaulting two other former partners.
He was jailed for 15 months and banned from driving for two years.
Allan also pleaded guilty to dangerous driving on roads between Snarestone and Ibstock, in North West Leicestershire, on June 21.
Tony Stanford, prosecuting, said the defendant began a relationship with the victim in 2012, when she was 16.
"They moved in together quite quickly, but the relationship broke down in its second year and she moved back to her parents," he said.
"He bombarded her with messages, including saying he couldn't live without her and was going to kill himself.
"He'd text her 20 to 30 times a day and attend her workplace, interrupting her work.
"The defendant also went to her home address and when her father wouldn't let him in, he damaged the father's car."
On the night of the crash, the teenager had left work at about midnight and as she drove home, saw headlights behind her.
After dropping a friend off in Swepstone village, she continued her journey.
At a junction, Allan pulled alongside and asked to speak to her, but she drove off.
"He followed her so closely she couldn't see his headlights in her rear mirror," said Mr Stanford.
"He'd drop back and accelerate close to the back of her vehicle, and at one point under-took, causing her to swerve all over the place, as he flashed his lights and pipped his horn."
The victim later told the police: "On Leicester Road, I felt him collide with the rear offside of my car.
"I was scared and decided to call the police while I carried on driving."
Mr Stanford said: "During this part of the journey he bumped into her four times."
In Penistone Street, Ibstock, he caused her to spin out of control and crash into a traffic light.
The teenager continued to talk over the phone to the police, and Allan left the scene.
Sentencing him, Judge Robert Brown told him: "Your record is worrying, featuring two convictions showing similarities in your behaviour towards ex-partners to try and dominate and control them."
Olwen Davies, mitigating, said Allan was "obsessed" by the teenager and "couldn't comprehend why she ended the relationship".
"He pursued her by car to stop her because he wanted to talk to her," she added.
"He's had negative experiences of relationships where people have been unfaithful in the past."
Mr Stanford then told the judge: "The complainant says his attitude towards her, and other women, was demonstrated by his regularly being unfaithful to her; bringing other women back to the house.
"It gives some insight into how he treats women."
Miss Davies said Allan now had a new girlfriend.
Judge Brown imposed an indefinite restraining order banning Allan from having any future contact with the victim.